Maximizing Power Output of a Partially Shaded Total-Cross-Tied Photovoltaic array

Neha Saurabh Shah, Hiren H Patel


Non-uniform conditions on the modules of the PV array, especially, partial shading reduces the output of the PV array to a large extent. The shaded module in a string limits the current of the entire string and hence, the output power of the string.  The output power under such conditions is reported to be higher for total-cross-tied (TCT) configuration. This paper describes two different approaches, one based on current compensation (current equalization) and another based on voltage equalization, to extract higher power from the partially shaded total-cross-tied photovoltaic array. The TCT configuration is considered to minimize the number of converters, sensors, cost and complexity involved. The additional converters in the two distinct approaches evaluated here operate only when the partial shading occurs and are controlled to minimize the current and voltage miss-matches. The analysis and the control algorithm are presented. Simulation results obtained in MATLAB/Simulink are included to demonstrate the effectiveness of both methods and the relative merits and demerits of these approaches are highlighted.


Current compensation; voltage equalization; MPPT; partial shading; TCT configuration

Full Text:



H. Patel and V. Agarwal, “MATLAB based modeling to study the effects of partial shading on PV array characteristics”, IEEE Trans. Energy Conversion, vol. 23, no.1, pp. 302-310, March 2008.

H.Patel and V. Agarwal, “Maximum power point tracking system forsystems operating under partially shaded condition”, IEEE Trans. Ind. Electron., vol. 55, no.4, pp.1689-1698, April 2008.

W.L. Chen and C.T. Tsai,” Optimal balancing control for tracking theoretical global MPP of series PV modules subject to Partial Shading”, IEEE Trans. Ind. Electron, vol. 62, no.8, pp.4837-4848, August 2015.

L. Gao, R. A. Dougal, S. Liu, and A. P. Iotova, “Parallel-connected solarPV system to address partial and rapidly fluctuating shadow conditions,”IEEE Trans. Ind. Electron., vol. 56, no. 5, pp. 1548–1556, May 2009.

F.Blaabjerg, R.Teodorescu, M.Liserre and A.V.Timbus, “Overview of control and grid synchronization for distributed power generationSystems”, IEEE Trans. Ind. Electron., vol.53, no.5, pp. 1398-1409, October 2006.

N.Femia, G. Lisi, G. Petrone, G. Spagnuolo, and M.Vitelli, “Distributedmaximum power point tracking of photovoltaic arrays : novel approachand system analysis”, IEEE Trans. Ind. Electron., vol.55, no.7, pp. 2610-2621, July 2008.

Z. Salam, M. Z. Ramli, “Distributed maximum power point tracker foradditional energy harvesting during partial shading of PV System”, IEEE conf. on Smart Grid and Renewable Energy (SGRE), pp. 1-5, March 2015.

G. AAdinolfi, G. Graditi, P. Siano, and A. Piccolo, “Multi-objectiveoptimal design of photovoltaic synchronous boost converters assessingefficiency, reliability and cost savings,” IEEE Trans. Ind. Informat., vol. 11, no. 5, pp. 1038–1048, October 2015.

Y. Nimni, D. Shmilovitz, “A retuned energy architecture for improvedphotovoltaic system efficiency”, IEEE Int. Symp. Circuits and Systems, Paris, pp. 2191-2194, June 2011.

Q. Zhang, X. Sun, Y. Zhong and M. Matsui “A novel topology for solving the partial shading problem in photovolatic power generation system,” IEEE 6th Int. Power Electron. Motion Control Conf. (IPEMC), Wuhan, pp. 2130-2135, May 2009.

P. Sharma, P.K. Peter and V. Agarwal, “Exact maximum power point tracking of partially shaded PV strings based on current equalization concept”, 38th IEEE Photovoltaic Specialists Conf., Austin, USA, pp. 1411-1416, June 2012.

P. Sharma and V. Agarwal, “Exact maximum power point tracking of grid-connected partially shaded PV source using current compensation concept,” IEEE Trans. Power Electron., vol. 29, no. 3, pp. 4684-4692, September 2014.

T. Shimizu, M. Hirakata, T. Kamezawa, and H. Watanabe, “Generation control circuit for photovoltaic modules,” IEEE Trans. Power Electron, vol. 16, pp. 293–300, May 2001.

T. Shimizu, O. Hashimoto, and G. Kimura, “A novel high-performance utility-interactive photovoltaic inverter system,” IEEE Trans. Power Electro, vol. 18, pp. 704–711, March 2003.

N. Shah and H. Patel, “Enhancing output power of PV array operating under non-uniform condition”, 16th IEEE Int. conf. on Environment and Electrical Engineering (EEEIC2016),Italy, pp. 1-6, June 2016.

M. Jazayeri, S. Uysal, and K. Jazayeri, "A Comparative study on different photovoltaic array topologies under partial shading conditions", IEEE PES T&D Conf. & Exposition, pp. 1-5, USA, April 2014.

B.J.G.Montano, D.J.F.Rombaoa, R.A.S.Peña and E.Q.B.Macabebe, “Effects of shading on current, voltage and power output of Total Cross-Tied photovoltaic array configuration”, 10 region IEEE conf. TENCON, Macao, pp.1-5, November 2015.

S. Vijayalakshmy, G.R. Bindu, S.R. Iyer, “Performance of partially shaded photovoltaic array configurations under shade dispersion”, IEEE Int. Conf. Advances in Green Energy (ICAGE), Trivandrum, pp. 50-55, December 2014.

B. I. Rani, G.S. Ilango and C. Nagamani,”Enhanced power generation from PV array under partial shading conditions by Shade dispersion using Su Do Ku configuration”, IEEE Trans. on Sustainable Energy, vol.4, no.3, pp.594-601, April 2013. [20] E.I. Batzelis, P.S. Georgilakis and S.A. Papathanassiou, “Energy models for photovoltaic systems under partialshading conditions: a comprehensive review”, IET Renew. Power Generation, vol. 9, no.4, pp. 340–349, 2015.

H. Sahu, S. Nayak, S. Mishra, “Maximizing the Power Generation of a Partially Shaded PV Array”, IEEE J. Emerging Sel. Topics Power Electron, vol.4, no.2, pp.626-637.June 2016.



  • There are currently no refbacks.

Copyright (c) 2017 Neha Saurabh Shah, Hiren H Patel

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

SSL Certificate